A, The effects of TNFα on apoptosis-related gene expression in human preadipocytes. Preadipocytes were treated with TNFα (0–10 nmol/L) for 8 h. mRNA expression was analyzed by RT-MPCR and normalized against GAPDH (internal control) and 18S rRNA (external control from parallel 18S-PCR). The upper panel shows a representative RT-MPCR. P < 0.01 at 1 nmol/L and above for each gene. B, The time course of TNFα (6 nmol/L) treatment of preadipocytes. Maximum increases in the expression of bcl-2, ICE, and NFκB were observed at 8 h (P < 0.01), and a maximum increase in TNFα expression was obtained at 1 h (P < 0.01).